The present invention relates to a process for producing a catalyst for xcex1-olefin polymerization and a process for producing an xcex1-olefin polymer.
As disclosed in JP-A 57-63310, JP-A 58-83006 and JP-A 61-78803, there is known a process for obtaining a highly stereoregular polymer by polymerizing an xcex1-olefin in the presence of a catalyst comprising a combination of the following catalyst components:
(1) a support type solid catalyst component obtained by supporting a tetravalent titanium halide compound on a magnesium halide,
(2) an organoaluminum compound (co-catalyst) and
(3) an organosilicon compound (third component).
Further, as disclosed in JP-A7-216017, there is also known a process for obtaining a highly stereoregular polymer by polymerizing an xcex1-olefin in the presence of a catalyst comprising a combination of the following catalyst components:
(1) a solid catalyst component obtained according to a process comprising the steps of:
(i) reducing a titanium compound with an organomagnesium compound in the presence of an organosilicon compound and an ester compound to obtaining a solid product,
(ii) treating said solid product with an ester compound, and
(iii) treating the treated product with either a mixture of an ether compound and titanium tetrachloride, or a mixture of an ether compound, titanium tetrachloride and an ester compound to obtain the desired solid catalyst component containing a trivalent titanium compound,
(2) an organoaluminum compound (co-catalyst) and
(3) an organosilicon compound (third component).
Furthermore, as disclosed in JP-A 10-212319, there is also known a process for obtaining a highly stereoregular polymer by polymerizing an xcex1-olefin in the presence of a catalyst comprising a combination of the following catalyst components:
(1) a solid catalyst component obtained according to a process comprising the steps of:
(i) reducing a titanium compound with an organomagnesium compound in the presence of an organosilicon compound and an ester compound to obtain a solid product,
(ii) treating said solid product with a mixture of an ether compound and titanium tetrachloride,
(iii) further treating the treated product with an organic acid halide compound, and
(iv) still further treating the resulting treated product with either a mixture of an ether compound and titanium tetrachloride, or a mixture of an ether compound, titanium tetrachloride and an ester compound to obtain the desired solid catalyst component containing a trivalent titanium compound,
(2) an organoaluminum compound (co-catalyst) and
(3) an organosilicon compound (third component).
According to the above-mentioned processes, a highly stereoregular polymer can be produced through a no-extraction/no-deash process. However, it is desired to further improve a quality of the highly stereoregular polymer.
Objects of the present invention are to provide a process for producing a polymerization catalyst suitable for obtaining a high quality xcex1-olefin polymer, and to provide a process for producing such an xcex1-olefin polymer.
The present invention provides a process for producing a catalyst for xcex1-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound and (3) a compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group in a closed ring structure with one another.
The present invention also provides a process for producing a catalyst for xcex1-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound, (3) a compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group and (4) an alkoxysilicon compound with one another.
The present invention also provides a process for producing a catalyst for xcex1-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound, (3) a compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group and (4) a 1,3-diether compound with one another.
The present invention also provides a process for producing a catalyst for xcex1-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound, (3) a compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group and (4) a piperidine compound with one another.
The present invention further provides a process for producing an xcex1-olefin polymer, which comprises the step of homopolymerizing or copolymerizing an xcex1-olefin in the presence of a catalyst for xcex1-olefin polymerization, which catalyst is obtained according to any of the above-mentioned processes for producing a catalyst for xcex1-olefin polymerization.
The compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group in a closed ring structure used in the present invention is a compound used as a so-called external donor. As such a compound, a compound represented by the following formula is exemplified. In the formula, R2 to R7 are independently of one another a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbyloxy group having 1 to 20 carbon atoms; and R1 and R8 are independently of each other a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbyloxy group having 1 to 20 carbon atoms, wherein both groups represented by R1 and R8 are bound with each other, or a left end carbon atom to which R1 is bound and a right end carbon atom to which R8 is bound are directly bound (in the latter case, neither R1 nor R8 exists). 
Examples of R2 to R7 are a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an i-propyl group, a n-butyl group, an i-butyl group, a tert-butyl, a n-pentyl group, an 1-pentyl group, a neopentyl group, a cyclopentyl group, a n-hexyl group, an 1-hexyl group, a cyclohexyl group, a n-heptyl group, a n-octyl group, 2-ethylhexyl group, a n-decyl group, an i-decyl group, a phenyl group, a methoxy group, an ethoxy group, a n-propoxy group, an i-propoxy group, a n-butoxy group, an i-butoxy group, a tert-butoxy group, a n-pentoxy group, an i-pentoxy group, a neopentoxy group, a n-hexoxy group and an i-hexoxy group.
Examples of a preferable compound represented by the above formula are 1,3-dioxolan, 2-methyl-1,3-dioxolan, 4-methyl-1,3-dioxolan, 2,2-dimethyl-1,3-dioxolan, 2,4-dimethyl-1,3-dioxolan, 2-methoxy-1,3-dioxolan, 4-methoxy-1,3-dioxolan, 2,2-dimethoxy-1,3-dioxolan, 1,3-dioxane, 2-methyl-1,3-dioxane, 4-methyl-1,3-dioxane, 2,2-dimethyl-1,3-dioxane, 2,4-dimethyl-1,3-dioxane, 2-methoxy-1,3-dioxane, 4-methoxy-1,3-dioxane, 2,2-dimethoxy-1,3-dioxane, 2,4-dimethoxy-1,3-dioxane, 1,3-dioxepane, 2-methyl-1,3-dioxepane, 4-methyl-1,3-dioxepane, 5-methyl-1,3-dioxepane, 2,4-dimethyl-1,3-dioxepane, 2,5-dimethyl-1,3-dioxepane, 2-methoxy-1,3-dioxepane, 4-methoxy-1,3-dioxepane, 5-methoxy-1,3-dioxepane and s-trioxane. Among them, particularly preferable is 1,3-dioxolan, 1,3-dioxane, 1,3-dioxepane or s-trioxane.
The compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group used in the present invention is a compound used as a so-called external donor. As such a compound, a compound represented by the above formula is exemplified. In the formula, R1 to R8 are independently of one another a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbyloxy group having 1 to 20 carbon atoms. Any groups represented by R1 to R8 may be bound with one another, and any two of three carbon atoms to which R1 to R8 are bound may be directly bound with each other. For example, a central carbon atom to which R4 is bound and a right end carbon atom to which R6 is bound may be directly bound with each other. In this case, neither R4 nor R6 exists. Examples of R1 to R8 are similar to those exemplified for the above-mentioned R2 to R7.
Examples of a compound wherein any combination of R1 to R8 has no bond therein are dimethylacetal, diethylacetal, propylenealdehyde dimethylacetal, n-octylaldehyde dimethyl acetal, benzaldehyde dimethylacetal, 2,2-dimethoxypropane, 3,3-dimethoxyhexane and 2,6-dimethyl-4,4-dimethoxyheptane.
Examples of compounds wherein any groups of R1 to R8 are bound to each other, or examples of compounds wherein any two carbon atoms of three carbon atoms having bonds to R1 to R8 are bound directly to each other are, as well as each compound exemplified above as a compound having the xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group in its closed ring structure, 1,1-dimethoxycyclopentane, 1,1-dimethoxycyclohexane, 1,1-diethoxycyclopentane, 1,1-diethoxycyclohexane, 2-methoxytrimethylene oxide, 2-ethoxytrimethylene oxide, 2,4-dimethoxytrimethylene oxide, 2,4-diethoxytrimethylene oxide, 2-methoxytetrahydrofuran, 2-ethoxytetrahydrofuran, 2,5-dimethoxytetrahydrofuran, 2,5-diethoxytetrahydrofuran, 2-methoxytetrahydropyran, 2-ethoxytetrahydropyran, 2,6-dimethoxytetrahydropyran and 2,6-diethoxytetrahydropyran. Among them, preferable is a compound wherein R1 and R8 are bound to each other, or a compound wherein R1 and R8 do not exist and two carbons bound to each of R1 and R8 are bound directly to each other, namely, a compound having a xe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94Oxe2x80x94Cxe2x80x94 bond group in a closed ring structure. Particularly preferable is 1,3-dioxolan, 1,3-dioxane, 1,3-dioxepane or s-trioxane.
A preferable example of the alkoxysilicon compound used in the present invention is that represented by the following formula. In the formula, R3 is a hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom or a hetero atom-containing substituent; R4 is a hydrocarbon group having 1 to 20 carbon atoms; r is a number satisfying 0xe2x89xa6r less than 4; and all R3s and all R4s are the same or different from each other, respectively.
R3rSi(OR4)4xe2x88x92r 
Examples of R3 as the hydrocarbon group in the above formula are straight chain alkyl groups such as methyl, ethyl, propyl, butyl and pentyl groups; branched chain alkyl groups such as isopropyl, sec-butyl, tert-butyl and tert-amyl groups; cycloalkyl groups such as a cyclopentyl group; cycloalkyl groups such as cyclopentyl and cyclohexyl groups; cycloalkenyl groups such as a cyclopentenyl group; and aryl groups such as phenyl and tolyl groups. Examples of R4 as the hydrocarbon group in the above formula are the same groups as these groups.
Examples of the hetero atom in R3 as the hetero atom-containing substituent in the above formula are an oxygen atom, a nitrogen atom, a sulfur atom and a phosphorus atom. Examples of the hetero atom-containing substituent are a dimethylamino group, a methylethylamino group, a diethylamino group, an ethyl-n-propylamino group, a di-n-propylamino group, a pyrrolyl group, a pyridyl group, a pyrrolidinyl group, a piperidinyl group, a perhydroindolyl group, a perhydroisoindolyl group, a perhydroquinolyl group, a perhydroisoquinolyl group, a perhydrocarbazoly group, a perhydroacridinyl group, a furil group, a pyranyl group, a perhydrofuril group and a thienyl group. Among them, preferable is a substituent wherein a hetero atom is able to make a direct bond to a silicon atom in an alkoxysilicon compound.
A preferable alkoxysilicon compound is an alkoxysilicon compound having at least one R3, which has a secondary or tertiary carbon atom bound directly to silicon atom in the above formula. Examples of preferable alkoxysilicon compounds are diisopropyl dimethoxysilane, diisobutyldimethoxysilane, di-tert-butyldimethoxysilane, tert-butylmethyldimethoxy silane, tert-butylethyldimethoxysilane, tert-butyl-n-propyldimethoxysilane, tert-butyl-n-butyldimethoxysilane, tert-amylmethyldimethoxy silane, tert-amylethyldimethoxysilane, tert-amyl-n-propyldimethoxysilane, tert-amyl-n-butyldimethoxysilane, isobutylisopropyl dimethoxysilane, tert-butylisopropyldimethoxysilane, dicyclobutyldimethoxysilane, cyclobutylisopropyldimethoxy silane, cyclobutylisobutyldimethoxysilane, cyclobutyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, cyclopentylisopropyl dimethoxysilane, cyclopentylisobutyldimethoxysilane, cyclopentyl-tert-butyldimethoxysilane, dicyclohexyl-dimethoxysilane, cyclohexylmethlydimethoxysilane, cyclohexylethlydimethoxysilane, cyclohexylisopropyl dimethoxysilane, cyclohexylisobutyldimethoxysilane, cyclo-hexyl-tert-butyldimethoxysilane, cyclohexylcyclopentyldimethoxy silane, cyclohexylphenyl-dimethoxysilane, diphenyldimethoxy silane, phenylmethyldimethoxysilane, phenylisopropyldimethoxy silane, phenylisobutyldimethoxysilane, phenyl-tert-butyldimethoxy silane, phenylcyclopentyldimethoxysilane, diisopropyl-diethoxysilane, diisobutyldiethoxysilane, di-tert-butyl-diethoxysilane, tert-butylmethyldiethoxysilane, tert-butylethyldiethoxysilane, tert-butyl-n-propyldiethoxy silane, tert-butyl-n-butyldiethoxysilane, tert-amylmethyldiethoxysilane, tert-amylethyldithoxysilane, tert-amyl-n-propyldiethoxysilane, tert-amyl-n-butyldiethoxy silane, dicyclopentyldiethoxysilane, dicyclohexyldiethoxy silane, cyclohexylmethlydiethoxysilane, cyclohexylethlydiethoxysilane, diphenyldiethoxysilane, phenylmethyldiethoxy silane, 2-norbornanemethyldimethoxysilane, bis(perhydroquinolino)dimethoxysilane, bis(perhydroisoquinolino)dimethoxysilane, (perhydroquinolino)(perhydroisoquinolino)dimethoxysilane, (perhydroquinolino)methyldimethoxysilane, (perhydroisoquinolino)methyldimethoxysilane, (perhydroquinolino)ethyldimethoxysilane, (perhydroisoquinolino)ethyldimethoxysilane, (perhydroquinolino)(n-propyl)dimethoxysilane, (perhydroisoquinolino)(n-propyl)dimethoxysilane, (perhydroquinolino)(tert-butyl)dimethoxysilane and (perhydroisoquinolino)(tert-butyl)dimethoxysilane.
The piperidine compound used in the present invention means a compound having a piperidine structure therein. As the compound, there can be exemplified a compound represented by the following formula. In the formula, R1 to R11 are independently of one another a hydrogen atom, or a straight chain, branched chain or alicyclic alkyl group having 1 to 20 carbon atoms. 
Examples of the compounds are 1-methylpiperidine, 1-ethyl piperidine, 1-n-propylpiperidine, 1-isopropylpiperidine, 2-methylpiperidine, 2-ethylpiperidine, 2-n-propylpiperidine, 2-isopropylpiperidine, 3-methylpiperidine, 3-ethylpiperidine, 3-n-propylpiperidine, 3-isopropylpiperidine, 4-methyl piperidine, 4-ethylpiperidine, 4-n-propyl piperidine, 4-isopropylpiperidine, 1,2-dimethylpiperidine, 1,3-dimethyl piperidine, 1,4-dimethylpiperidine, 2,3-dimethylpiperidine, 2,3-diethylpiperidine, 2,4-dimethylpiperidine, 2,4-diethyl piperidine, 2,5-dimethylpiperidine, 2,5-diethylpiperidine, 2,6-dimethylpiperidine, 2,6-diethyl piperidine, 2,6-n-propyl piperidine, 2,6-diisopropylpiperidine, 2,4,6-trimethylpiperidine, 2,2,6,6-tetramethylpiperidine, 2,2,6,6-tetraethylpiperidine and a combination of two or more thereof. Among them, preferable is 2,6-dimethylpiperidine or 2,2,6,6-tetramethylpiperidine.
The solid catalyst component used in the present invention may be that known in the art. Examples of the solid catalyst component acre those disclosed in JP-B 46-34092, JP-B 47-41676, JP-B55-23561, JP-B57-24361, JP-B52-39431, JP-B52-36786, JP-B 1-28049, JP-B3-43283, JP-A4-80044, JP-A55-52309, JP-A58-21405, JP-A 61-181807, JP-A 63-142008, JP-A 5-339319, JP-A 54-148093, JP-A 4-227604, JP-A 6-2933, JP-A 64-6006, JP-A 6-179720, JP-B 7-116252, JP-A 8-134124, JP-A 9-31119, JP-A 11-228628, JP-A 11-80234 and JP-A 11-322833.
A preferable solid catalyst component is that having further an electron donor as well as Ti, Mg and halogen atoms. As the electron donor, organic acid esters or ethers are preferable, both of which are mentioned hereinafter.
As a process for producing the solid catalyst component, the following processes 1 to 5 are exemplified. Of these, the process 5 is preferred.
Process 1: process comprising the step of contacting a magnesium halide compound and a titanium compound with each other.
Process 2: process comprising the step of contacting a magnesium halide compound, an electron donor and a titanium compound with one another.
Process 3: process comprising the steps of (i) dissolving a magnesium halide compound and a titanium compound in an electron donating solvent to form a solution, and then (ii) impregnating the solution to a carrier substance.
Process 4: process comprising the step of contacting a dialkoxymagnesium compound, a titanium halide compound and an electron donor with one another.
Process 5: process comprising the step of contacting a solid component containing a magnesium atom, a titanium atom and a hydrocarbyloxy group, a halogenocompound and an electron donor and/or an organic acid halide with one another.
The above-mentioned solid component is a solid substance containing at least a magnesium atom, a titanium atom and a hydrocarbyloxy group. A content of the hydrocarbyloxy group in the solid component is preferably not less than 20% by weight, and more preferably not less than 25% by weight, provided that an amount of the solid component is 100% by weight.
A preferable solid component is that obtained by reducing a titanium compound represented by the following formula [I] with an organomagnesium compound in the presence of an organosilicon compound having an Sixe2x80x94O bond. In this case, it is preferable that an ester compound as an optional component coexists from a view point of improving a polymerization activity and a stereoregular polymerization ability of a polymerization catalyst obtained. In the following formula [I] a is a number of 1 to 20, preferably 1xe2x89xa6axe2x89xa65, and more preferably 1, 2 or 4; R2 is a hydrocarbon group having 1 to 20 carbon atoms; and X2 is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, wherein all X2s may be the same or different from each other. 
Examples of the above-mentioned organosilicon compound are those represented by the following formulas. In these formulas, R10 is a hydrocarbon group having 1 to 20 carbon atoms; R11, R12, R13, R14 and R15 are independently of one another a hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom; t is a number satisfying 0 less than txe2x89xa64; u is an integer of from 1 to 1000; and v is an integer of from 2 to 1000.
Si(OR10)tR114xe2x88x92t, 
R12(R132SiO)uSiR143 and 
(R152SiO)v 
Specific examples of the organosilicon compound are tetramethoxysilane, dimethyldimethoxysilane, tetraethoxysilane, triethoxyethylsilane, diethoxydiethylsilane, ethoxytriethylsilane, tetra-i-propoxysilane, di-i-propoxy-di-i-propylsilane, tetrapropoxysilane, dipropoxydipropylsilane, tetrabutoxysilane, dibutoxydibutylsilane, dicyclopentoxydiethylsilane, diethoxydiphenylsilane, cyclohexyloxytrimethylsilane, phenoxytrimethylsilane, tetraphenoxysilane, triethoxyphenylsilane, hexamethyldisiloxane, hexaethyldisiloxane, hexapropyldisiloxane, octaethyltrisiloxane, dimethyl polysiloxane, diphenyl polysiloxane, methylhydro polysiloxane and phenylhydro polysiloxane.
Among the above-mentioned three formulas, preferable are alkoxysilane compounds represented by the first formula, wherein t is preferably a number satisfying 1xe2x89xa6txe2x89xa64. Of these, tetraalkoxysilane compounds of t=4 are particularly preferred, and the most preferred is tetraethoxysilane.
Examples of R2 in the above formula [I] are alkyl groups such as methyl, ethyl, propyl, i-propyl, butyl, i-butyl, amyl, i-amyl, hexyl, heptyl, octyl, decyl and dodecyl groups; aryl groups such as phenyl, cresyl, xylyl and naphthyl groups; cycloalkyl groups such as cyclohexyl and cyclopentyl groups; allyl groups such as a propenyl group; and aralkyl groups such as a benzyl group. Among these, alkyl groups having 2 to 18 carbon atoms or aryl groups having 6 to 18 carbon atoms are preferred, and straight chain alkyl groups having 2 to 18 carbon atoms are particularly preferred.
As the halogen atom represented by X2 in the above formula [I], a chlorine atom, a bromine atom and an iodine atom are exemplified. Of these, a chlorine atom is particularly preferred. As the hydrocarbyloxy groups having 1 to 20 carbon atoms represented by X2, there are exemplified the hydrocarbyloxy groups having the same groups as R2""s mentioned above. An alkoxy group having a straight chain alkyl group of 2 to 18 carbon atoms is particularly preferred as X2.
Examples of titanium compounds represented by the above formula [I] are tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetra-iso-propoxytitanium, tetra-n-butoxytitanium, tetra-iso-butoxytitanium, n-butoxytitaniumtrichloride, di-n-butoxytitaniumdichloride, tri-n-butoxytitanium chloride, di-n-tetraisopropyl polytitanate (a mixture of compounds of a=2 to 10), tetra-n-butyl polytitanate (a mixture of compounds of a=2 to 10), tetra-n-hexyl polytitanate (a mixture of compounds of a=2 to 10), tetra-n-octyl polytitanate (a mixture of compounds of a=2 to 10), a condensate of a tetraalkoxytitanium obtained by reacting a tetralkoxytitanium with a small amount of water, and a combination of at least two of these compounds. Among them, particularly preferable is tetra-n-butoxytitanium, tetra-n-butyltitanium dimer or tetra-n-butyltitanium tetramer.
The above-mentioned organomagnesium compound means any organomagnesium compound having a magnesium-carbon bond. Among them, a Grignard compound or a dihydrocarbyl magnesium represented by the following formulas is particularly preferable. In the formulas, Mg is a magnesium atom; each of R16, R17 and R18 is a hydrocarbon group having 1 to 20 carbon atoms, and R17 and R18 may be the same or different from each other; and X5 is a halogen atom.
R16MgX5 
R17R18Mg 
Specific examples of R16 to R18 are alkyl, aryl, aralkyl and alkenyl groups having 1 to 20 carbon atoms such as methyl, ethyl, propyl, 1-propyl, butyl, sec-butyl, tert-butyl, i-amyl, hexyl, octyl, 2-ethylhexyl, phenyl and benzyl groups. It is particularly recommendable to use the Grignard compound in the form of an ether solution thereof from a viewpoint of performance of the catalyst obtained.
It is permitted to use the organomagnesium compound in combination with an organometallic compound to form a hydrocarbon soluble complex. Examples of the organometallic compounds are compounds of Li, Be, B, Al and Zn.
As the above-mentioned ester compound, a mono-carboxylic acid ester and a poly-carboxylic acid ester are exemplified. As these compounds, for example, saturated aliphatic carboxylic acid esters, unsaturated aliphatic carboxylic acid esters, alicyclic carboxylic acid esters and aromatic carboxylic acid esters are enumerated.
Specific examples of the ester compounds are methyl acetate, ethylacetate, phenylacetate, methylpropionate, ethyl propionate, ethyl butyrate, ethyl valerate, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl benzoate, butyl benzoate, methyl toluate, ethyl toluate, ethyl anisate, diethyl succinate, dibutyl succinate, diethyl malonate, dibutyl malonate, dimethyl maleate, dibutyl maleate, diethyl itaconate, dibutyl itaconate, monoethyl phthalate, dimethyl phthalate, methyl ethyl phthalate, diethyl phthalate, di-n-propyl phthalate, di-i-propyl phthalate, di-n-butyl phthalate, di-i-butyl phthalate, di-n-octyl phthalate and diphenyl phthalate. Among them, unsaturated aliphatic carboxylic acid esters such as methacrylic acid esters and maleic acid esters, and aromatic carboxylic acid esters such as phthalic acid esters are preferred. Dialkyl phthalates are particularly preferred.
The titanium compound, the organosilicon compound and the ester compound are preferably dissolved in or diluted with a suitable solvent, and then used. Examples of the solvent are aliphatic hydrocarbons such as hexane, heptane, octane and decane; aromatic hydrocarbons such as toluene and xylene; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane and decalin; and ether compounds such as diethyl ether, dibutyl ether, di-i-amyl ether and tetrahydrofuran.
A temperature of the reduction reaction is usually from xe2x88x9250 to 70xc2x0 C., preferably from xe2x88x9230 to 50xc2x0 C., and particularly preferably from xe2x88x9225 to 35xc2x0 C. A time required for the reduction reaction is not particularly limited, and it is usually from about 30 minutes to about 6 hours. After the reaction is carried out at the above-mentioned temperature, it is permitted to further carry out a post-reaction at a temperature of from 20 to 120xc2x0 C.
Those compounds used in the reduction reaction may be used in combination with a porous carrier such as an inorganic oxide or an organic polymer, in order that the obtained solid product is impregnated in the porous carrier. The porous carrier may be a conventional one. Examples of the porous carrier are porous inorganic oxides such as SiO2, Al2O3, MgO, TiO2 and ZrO2; and organic porous polymers such as polystyrene, styrene-divinylbenzene copolymer, styrene-ethylene glycol-methyl dimethacrylate copolymer, polymethyl acrylate, polyethyl acrylate, methyl acrylate-divinylbenzene copolymer, polymethyl methacrylate, methyl methacrylate-divinylbenezene copolymer, polyacrylonitrile, acrylonitrile-divinylbenezene copolymer, polyvinyl chloride, polyethylene and polypropylene. Of these, preferred are organic porous polymers, and particularly preferred is a styrene-divinylbenzene copolymer or an acrylonitrile-divinylbenzene copolymer.
A pore volume of the porous carrier in a pore radius of from 200 to 2000 xc3x85 is preferably not less than 0.3 cc/g and more preferably not less than 0.4 cc/g; and a ratio of said pore volume to a pore volume in a pore radius of from 35 to 75000 xc3x85 is preferably not less than 35% and more preferably not less than 40%. When said pore volume is less than 0.3 cc/g or the ratio is less than 35%, the solid product may not be impregnated effectively in the porous carrier.
The organosilicon compound is used in an amount of usually from 1 to 500, preferably from 1 to 300, and particularly preferably from 3 to 100 in terms of an atomic ratio, Si/Ti, i.e. a ratio of a silicon atom in the organosilicon compound to a titanium atom in the titanium compound used.
The organomagnesium compound is used in an amount of usually from 0.1 to 10, preferably from 0.2 to 5.0, and particularly preferably from 0.5 to 2.0 in terms of an atomic ratio, (Ti+Si)/Mg, i.e. a ratio of the sum of a titanium atom in the titanium compound used and a silicon atom in the organosilicon compound used to a magnesium atom in the organomagnesium compound.
Each of the titanium compound, the organosilicon compound and the organomagnesium compound may be used in an amount of usually from 1 to 51, preferably from 2 to 31, and particularly preferably from 4 to 26 in terms of an atomic ratio, Mg/Ti, i.e. a ratio of a magnesium atom in the solid catalyst component obtained to a titanium atom therein.
The ester compound (optional component) is used in an amount of usually from 0.5 to 100, preferably from 1 to 60, and particularly preferably from 2 to 30 in terms of a molar ratio, ester compound/Ti, i.e. a ratio of the ester compound used to a titanium atom in the titanium compound used.
The solid product obtained by the reduction reaction is usually separated by solid-liquid separation, and washed several times with an inert hydrocarbon solvent such as hexane, heptane and toluene.
The solid component comprises a three valence titanium atom, a magnesium atom and a hydrocarbyloxy group, and generally shows an amorphous state or a very week crystalline state. In view of catalyst performance, an amorphous solid component is particularly preferable.
The halogenocompound having halogenation ability used in the present invention means any compound, which is able to substitute the hydrocarbyloxy group in the solid component with a halogen atom thereof. Among them, a halogenocompound of the Group 4 elements, a halogenocompound of the Group 13 elements or a halogenocompound of the Group 14 elements is preferable.
As the halogenocompound of the Group 4 elements, those represented by the following formula are preferable. In this formula, M is a Group 4 element; R9 is a hydrocarbon group having 1 to 20 carbon atoms; X4 is a halogen atom; and b is a number satisfying 0xe2x89xa6bxe2x89xa64, preferably 0xe2x89xa6bxe2x89xa62, and particularly preferably b=0. Examples of M are Ti, Zr and Hf, and Ti is preferable.
M(OR9)bX44xe2x88x92b 
Examples of R9 are alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, amyl, isoamyl, tert-amyl, hexyl, heptyl, octyl, decyl and dodecyl groups; aryl groups such as phenyl, cresyl, xylyl and naphthyl groups; allyl groups such as a propenyl group; and aralkyl groups such as a benzyl group. Among them, alkyl groups having 2 to 18 carbon atoms or aryl groups having 6 to 18 carbon atoms are preferred, and straight chain alkyl groups having 2 to 18 carbon atoms are particularly preferred. The halogen compound of the Group 4 elements may be a compound having at least two OR9 groups different from one another.
As X4 in the above formula, a chlorine atom, a bromine atom and an iodine atom are exemplified. Of these, a chlorine atom is particularly preferred.
Specific examples of the halogenocompound represented by the above formula are titanium tetrahalides such as titanium tetrachloride, titanium tetrabromide and titanium tetraiodide; alkoxytitanium trihalides such as methoxytitanium trichloride, ethoxytitanium trichloride, butoxytitanium trichloride, phenoxytitanium trichloride and ethoxytitanium tribromide; dialkoxytitanium dihalides such as dimethoxytitanium dichloride, diethoxytitanium dichloride, dibutoxytitanium dichloride, diphenoxytitanium dichloride and diethoxytitanium dibromide; and those obtained by changing xe2x80x9ctitaniumxe2x80x9d in the above compounds to zirconium or hafnium. Among these compounds, the most preferred is titanium tetrachloride.
As the halogenocompound of the Group 13 elements or the halogenocompound of the Group 14 elements, those represented by the following formula are preferable. In the formula, M is the Group 13 or 14 element; R is a hydrocarbon group having 1 to 20 carbon atoms; X is a halogen atom such as F, Cl, Br and I, and among them Cl is preferable; m is a valence of M (for example, when M is Si, m is 4); and a is a number satisfying 0 less than axe2x89xa6m (for example, when M is Si, a is preferably 3 or 4).
MRm-aXa 
As the Group 13 elements, B, Al, Ga, In and Tl are exemplified. Of these, preferred is B or Al, and more preferred is Al. As the Group 14 element, C, Si, Ge, Sn and Pb are exemplified. Of these, preferred is Si, Ge or Sn.
As R in the above formula, there are exemplified alkyl groups such as a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, an amyl group, an isoamyl group, a hexyl group, a heptyl group, an octyl group, a decyl group and a dodecyl group; aryl groups such as a phenyl group, a tolyl group, a cresyl group, a xylyl group and a naphthyl group; cycloalkyl groups such as a cyclohexyl group and cyclopentyl group; allyl groups such as a propenyl group; and aralkyl groups such as a benzyl group. Of these, alkyl groups or aryl groups are preferred, and a methyl group, an ethyl group, a n-propyl group, a phenyl group or a p-tolyl group is particularly preferred.
As the halogenocompound of the Group 13 elements, there are exemplified trichloroboron, methyldichloroboron, ethyldichloroboron, phenyldichloroboron, cyclohexyldichloroboron, dimethylchloroboron, methylethylchloroboron, trichloroaluminum, methyldichloroaluminum, ethyldichloroaluminum, phenyldichloroaluminum, cyclohexyldichloroaluminum, dimethylchloroaluminum, diethylchloroaluminum, methylethylchloroaluminum, ethylaluminum sesquichloride, gallium chloride, gallium dichloride, trichlorogallium, methyldichlorogallium, ethyldichlorogallium, phenyldichlorogallium, cyclohexyldichlorogallium, dimethylchlorogallium, methylethylchlorogallium, indium chloride, indium trichloride, methylindium dichloride, phenylindium dichloride, dimethylindium chloride, thallium chloride, thallium trichloride, methylthallium dichloride, phenylthallium dichloride, dimethylthallium chloride, and compounds formed by replacing the chloro in the above compounds with fluoro, bromo or iodo.
Specific examples of the halogenocompounds of the group 14 elements are tetrachloromethane, trichloromethane, dichloromethane, monochloromethane, 1,1,1-trichloroethane, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, tetrachlorosilane, trichlorosilane, methyltrichlorosilane, ethyltrichlorosilane, n-propyltrichlorosilane, n-butyltrichlorosilane, phenyltrichlorosilane, benzyltrichlorosilane, p-tolyltrichlorosilane, cyclohexyltrichlorosilane, dichlorosilane, methyldichlorosilane, ethyldichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, methylethyldichlorosilane, monochlorosilane, trimethylchlorosilane, triphenylchlorosilane, tetrachlorogermane, trichlorogermane, methyltrichlorogermane, ethyltrichlorogermane, phenyltrichlorogermane, dichlorogermane, dimethyldichlorogermane, diethyldichlorogermane, diphenyldichlorogermane, monochlorogermane, trimethylchlorogermane, triethylchlorogermane, tri-n-butylchlorogermane, tetrachlorotin, methyltrichlorotin, n-butyltrichlorotin, dimethyldichlorotin, di-n-butyldichlorotin, di-i-butyldichlorotin, diphenyldichlorotin, divinyldichlorotin, methyltrichlorotin, phenyltrichlorotin, dichlorolead, methylchlorolead and phenylchlorolead, and compounds named by replacing the chloro in the above named compounds with F, Br and I, respectively.
As the halogenocompound, particularly preferred is tetrachlorotitanium, methyldichloroaluminum, ethyldichloroaluminum, tetrachlorosilane, phenyltrichlorosilane, methyltrichlorosilane, ethyltrichlorosilane, n-propyltrichlorosilane or tetrachlorotin, from a viewpoint of polymerization activity. The above compounds may be used in combination of two or more thereof.
When an electron donor is used in the present invention, a polymerization catalyst, which produces a more highly stereoregular polymer, can be obtained.
Examples of the electron donor are oxygen-containing electron donor compounds such as ethers, ketones, aldehydes, carboxylic acids, organic acid esters, inorganic acid esters, organic acid amides, inorganic acid amides and acid anhydrides; and nitrogen-containing electron donor compounds such as ammonia, amines, nitriles and isocyanates. Of these, organic acid esters, ethers or a combination thereof are preferred, and carboxylic acid esters, ethers or a combination thereof are more preferred.
As the carboxylic acid esters, for example, mono-carboxylic acid esters and poly-carboxylic acid esters are enumerated. More specifically, saturated aliphatic carboxylic acid esters, unsaturated aliphatic carboxylic acid esters, alicyclic carboxylic acid esters and aromatic carboxylic acid esters are enumerated.
Specific examples of the carboxylic acid esters are methyl acetate, ethyl acetate, phenyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, ethyl valerate, ethyl acrylate, methyl methacrylate, ethyl benzoate, butyl benzoate, methyl toluate, ethyl toluate, ethyl anisate, diethyl succinate, dibutyl succinate, diethyl malonate, dibutyl malonate, dimethyl maleate, dibutyl maleate, diethyl itaconate, dibutyl itaconate, monoethyl phthalate, dimethyl phthalate, methyl ethyl phthalate, diethyl phthalate, di-n-propyl phthalate, di-i-propyl phthalate, di-n-butyl phthalate, di-i-butyl phthalate, di-n-octyl phthalate and diphenyl phthalate. Among these carboxylic acid esters, unsaturated aliphatic carboxylic acid esters such as methacrylic acid esters and maleic acid esters, and aromatic carboxylic acid esters such as benzoic acid esters and phthalic acid esters are preferred. Aromatic polycarboxylic acid esters are particularly preferred, and dialkyl phthalates are most preferred.
Preferable examples of the ethers are dialkyl ethers, diethers represented by the following formula and a combination of two or more thereof. In the formula, R5 to R8 are independently of one another a straight chain alkyl group, a branched chain alkyl group, an alicyclic group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, provided that R6 and R7 may be independently of each other a hydrogen atom. 
Preferable examples of the ethers are dimethyl ether, diethyl ether, di-n-butyl ether, methyl ethyl ether, methyl-n-butyl ether, methyl cyclohexyl ether, 2,2-di-i-butyl-1,3-dimethoxypropane, 2-i-propyl-2-i-pentyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, 2-i-propyl-2-3,7-dimethyloctyl-1,3-dimethoxypropane, 2,2-di-i-propyl-1,3-dimethoxypropane, 2-i-propyl-2-cyclohexylmethyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2-i-propyl-2-i-butyl-1,3-dimethoxypropane, 2,2-di-i-propyl-1,3-dimethoxypropane, 2,2-di-propyl-1,3-dimethoxypropane, 2-i-propyl-2-cyclohexyl-1,3-dimethoxypropane, 2-i-propyl-2-cyclopentyl-1,3-dimethoxypropane, 2,2-di-cyclopentyl-1,3-dimethoxypropane and 2-heptyl-2-pentyl-1,3-dimethoxypropane, and a combination of two or more thereof.
As the ethers, dialkyl ethers are particularly preferred, and di-n-butyl ethers are most preferred. Hereinafter, di-n-butyl ethers is simply referred to as dibutyl ether or butyl ether.
The 1,3-diether compound used in the present invention means a compound having a 1,3-dialkoxypropane structure therein. Examples of the compound are those wherein R5 to R8 in the diether compound represented by the above formula are independently of one another an alkyl group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, provided that R6 and R7 may be independently of each other a hydrogen atom.
Specific examples of the compound are 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxy propane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, 2-isopropyl-2-3,7-dimethyloctyl-1,3-dimethoxy propane, 2,2-diisopropyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclo hexylmethyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2-isopropyl-2-isobutyl-1,3-dimethoxy propane, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-dipropyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclohexyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclopentyl-1,3-dimethoxy propane, 2,2-dicyclopentyl-1,3-dimethoxypropane, 2-heptyl-2-pentyl-1, 3-dimethoxy propane, and a combination of two or more thereof. Among them, preferable is 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-diisopropyl-1,3-dimethoxypropane or 2,2-dicyclohexyl-1,3-dimethoxypropane.
As the organic acid halide used in the present invention, preferable is a monocarboxylic acid halide or a polycarboxylic acid halide. As the organic acid halides, aliphatic carboxylic acid halides, alicyclic carboxylic acid halides and aromatic carboxylic acid halides are enumerated. Specific examples thereof are acetyl chloride, propionic chloride, butyric chloride, valeric chloride, acrylic chloride, methacrylic chloride, benzoic chloride, toluic chloride, anisic chloride, succinic chloride, malonic chloride, maleic chloride, itaconic chloride and phthalic chloride. Of these, aromatic carboxylic acid chlorides such as benzoic chloride, toluic chloride and phthalic chloride are preferred. Aromatic dicarboxylic acid dichlorides are more preferred, and phthalic chloride is particularly preferred.
The contact in the above-mentioned process 5 is usually carried out in an atmosphere of an inert gas such as nitrogen and argon. Examples of the contacting method are as follows.
Method (1): method comprising the step of adding the halogenocompound and the electron donor to the solid component to effect the contact, wherein an addition order is limited.
Method (2): method comprising the step of adding the halogenocompound and the organic acid halide to the solid component to effect the contact, wherein an addition order is limited.
Method (3): method comprising the step of adding a mixture of the halogenocompound, the electron donor and the organic acid halide to the solid component to effect the contact.
Method (4): method comprising the step of adding a mixture of the halogenocompound and the electron donor, and the organic acid halide to the solid component to effect the contact, wherein an addition order is limited.
Method (5): method comprising the steps of (i) adding the electron donor to the solid component to effect the contact, and thereafter (ii) adding thereto the halogenocompound to effect the contact.
Method (6): method comprising the steps of (i) adding the electron donor to the solid component to effect the contact, and thereafter (ii) adding thereto the halogenocompound and the electron donor to effect the contact, wherein an addition order is limited.
Method (7): method comprising the steps of (i) adding the electron donor to the solid component to effect the contact, and thereafter (ii) adding thereto a mixture of the halogenocompound and the electron donor to effect the contact.
Method (8): method comprising the step of adding the solid component and the electron donor to the halogenocompound to effect the contact, wherein an addition order is limited.
Method (9): method comprising the step of adding the solid component and the organic acid halide to the halogenocompound to effect the contact, wherein an addition order is limited.
Method (10): method comprising the step of adding the solid component, the electron donor and the organic acid halide to the halogenocompound to effect the contact, wherein an addition order is limited.
As the contacting methods, for example, (1) a method comprising the step of further carrying out at least one time contact with the halogenocompound after completion of any of methods mentioned above, and (2) a method comprising the step of further carrying out at least one time contact with a mixture of the halogenocompound and the electron donor compound after completion of any of methods mentioned above are further given.
Among these methods mentioned above, preferred are the method (2); the method (4); a method comprising the step of further carrying out at least one time contact with a mixture of the halogenocompound and the electron donor after completion of the method (4); and the method (7). Among these four methods, more preferred are the latter three methods. Particularly preferred are (1) a method comprising the steps of (i) adding a mixture of the halogenocompound and the ether, and the organic acid halide in this order to the solid component to effect the contact, thereafter (ii) adding thereto a mixture of the halogenocompound, the carboxylic acid ester and the ether to effect the contact, and further (iii) carrying out at least one time contact with a mixture of the halogenocompound and the ether, and (2) a method comprising the steps of (i) adding the carboxylic acid ester to the solid component to effect the contact, thereafter (ii) adding therto a mixture of the halogenocompound, the carboxylic acid ester and the ether to effect the contact, and further (iii) carrying out at least one time contact with a mixture of the halogenocompound and the ether.
How to contact is not limited. For example, a mechanical pulverization method using an apparatus such as a ball mill and a slurry method are given. The former method is not preferred from an industrial point of view, because the obtained solid catalyst component may contain a lot of fine powders, and as a result, a particle size distribution thereof may be broad. Thus, preferred is a method wherein the contact is carried out in the presence of a diluent. The solid catalyst component obtained according to the contact mentioned above can be used as it is. However, it is recommendable to wash the component obtained preferably with a diluent inert thereto, thereby removing unnecessaries in the component.
Examples of the diluent are aliphatic hydrocarbons such as pentane, hexane, heptane and octane; aromatic hydrocarbons such as benzene, toluene and xylene; alicyclic hydrocarbons such as cyclohexane and cyclopentane; and halogenated hydrocarbons such as 1,2-dichloroethane and monochlorobenzene.
An amount of the diluent used per one contact is usually from 0.1 ml to 1000 ml, and preferably from 1 ml to 100 ml, per 1 g of the solid component. An amount of the diluent used per one washing is almost the same as that mentioned above. Washing is carried out usually from 1 to 5 times per one contact.
A temperature at which contacting and washing are carried out is usually from xe2x88x9250 to 150xc2x0 C., preferably from 0 to 140xc2x0 C., and more preferably from 60 to 135xc2x0 C. A contact time is not particularly limited, and preferably from 0.5 to 8 hours, and more preferably from 1 to 6 hours. A washing time is not also particularly limited, and preferably from 1 to 120 minutes, and more preferably from 2 to 60 minutes.
An amount of the halogenocompound used is usually from 0.5 to 1000 mmol, preferably from 1 to 200 mmol, and more preferably from 2 to 100 mmol, per 1 g of the solid component.
It is recommendable to use the halogenocompound in combination with the electron donor. In such a case, the electron donor is used in an amount of usually from 1 to 100 mol, preferably from 1.5 to 75 mol, and more preferably from 2 to 50 mol, per one mol of the halogenocompound.
The amount of the electron donor is usually from 0.01 to 100 mmol, preferably from 0.05 to 50 mmol, and more preferably from 0.1 to 20 mmol, per one g of the solid component. When the amount exceeds 100 mmol, the solid component particle may collapse.
The organic acid halide is used in an amount of usually from 0.1 to 100 mmol, preferably from 0.3 to 50 mmol, and more preferably from 0.5 to 20 mmol, per one g of the solid component; and usually from 0.01 to 1.0 mol and preferably from 0.03 to 0.5 mol, per one mol of the magnesium atom in the solid component. When the former amount exceeds 100 mmol or the latter amount exceeds 1.0 mol, the solid component particle may collapse.
When two or more kinds of compounds mentioned above are used in more than one time contact, the amount mentioned above for respective compounds is that per one contact.
In using for the polymerization, the solid catalyst component obtained may be combined with an inert diluent to form a slurry, or may be dried to obtain a flowable powder. As a drying method, a method wherein a volatile matter is removed under reduced pressure, and a method wherein a volatile matter is removed under stream of an inert gas such as nitrogen and argon are exemplified. A drying temperature is preferably from 0 to 200xc2x0 C., and more preferably from 50 to 100xc2x0 C. A drying period of time is preferably from 0.01 to 20 hours, and more preferably from 0.5 to 10 hours.
The organoaluminum compound used in the present invention means a compound having at least one Al-carbon bond therein. Typical examples thereof are those represented by the following formulas. In the formulas, R19 to R23 are independently of one another a hydrocarbon group having 1 to 20 carbon atoms; Y is a halogen atom, a hydrogen atom or an alkoxy group; and w is a number satisfying 2xe2x89xa6wxe2x89xa63.
R19wAlY3xe2x88x92w 
R20R21Alxe2x80x94Oxe2x80x94AlR22R23 
Specific examples of the organoaluminum compound are trialkylaluminums such as triethylaluminum, tri-i-butylaluminum and trihexylaluminum; dialkylaluminum hydrides such as diethylaluminum hydride and di-i-butylaluminum hydride; dialkylaluminum halides such as diethylaluminum chloride; mixtures of trialkylaluminums and dialkylaluminum halides such as a mixture of triethylaluminum and diethylaluminum chloride; and alkylalumoxanes such as tetraethyldialumoxane and tetrabutyldialumoxane.
Among these, trialkylaluminums, mixtures of trialkylaluminums with dialkylaluminum halides, or alkylalumoxanes is preferred. Triethylaluminum, tri-i-butylaluminum, a mixture of triethylaluminum with diethylaluminum chloride, or tetraethyldialumoxane is particularly preferred.
The xcex1-olefin used in the present invention means an xcex1-olefin having at least 3 carbon atoms. Examples thereof are straight chain mono-olefins such as propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1 and decene-1; branched chain mono-olefins such as 3-methylbutene-1,3-methylpentene-1 and 4-methylpentene-1; vinylcyclohexane; and a combination of two or more thereof.
Of these, preferred is a homopolymerization of propylene or butene-1, or a copolymerization of a mixed olefin containing propylene or butene-1 as a main component, and particularly preferred is a homopolymerization of propylene, or a copolymerization of a mixed olefin containing propylene as a main component. In the copolymerization, (1) it is permitted to use a combination of at least two olefins selected from the group consisting of ethylene and the above-mentioned xcex1-olefins or a combination of said olefin and a polyunsaturated bond-carrying compound such as a conjugated diene and a non-conjugated diene, and (2) it is permitted to carry out a hetero-block copolymerization through a two or more stage polymerization.
The catalyst for xcex1-olefin polymerization used in the present invention can be obtained by contacting the above-mentioned solid catalyst component, organoaluminum compound and external donor with one another. How to contact them is not limited as far as said catalyst for polymerization can be obtained. For example, (1) a method wherein those three components per se are contacted with one another, (2) a method wherein those three components are respectively diluted with a solvent, followed by contact with one another, and (3) a method wherein those three components are separately supplied to a polymerization vessel, followed by contact with one another in the polymerization vessel are given. It is preferred that respective components are supplied to the polymerization vessel under water free conditions using an inert gas such as nitrogen and argon. It is permitted that any two or three of those three components are contacted in advance, and those contacted are supplied to the polymerization vessel.
In the process for producing an xcex1-olefin polymer of the present invention, the above-mentioned catalyst itself may be used (said polymerization is hereinafter referred to as xe2x80x9creal polymerizationxe2x80x9d). Alternatively, a pre-polymerized polymerization catalyst obtained by the below-mentioned pre-polymerization of said catalyst may be used for the real polymerization.
The pre-polymerized polymerization catalyst can usually be obtained by polymerizing (namely, pre-polymerizing) a small amount of an olefin in the presence of the above-mentioned solid catalyst component and organoaluminum compound. As a pre-polymerization process, it is recommendable to carry out a slurry polymerization process, wherein an inert hydrocarbon such as propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, cyclohexane, benzene and toluene is used as a solvent. The solvent may be partially or totally replaced with a liquefied olefin.
An amount of the organoaluminum compound used in the pre-polymerization is usually from 0.5 to 700 mol, preferably from 0.8 to 500 mol, and particularly preferably from 1 to 200 mol, per 1 mol of the titanium atom contained in the solid catalyst component.
An amount of the olefin pre-polymerized is usually from 0.01 to 1000 g, preferably from 0.05 to 500 g, and particularly preferably from 0.1 to 200 g, per 1 g of the solid catalyst component.
A slurry concentration in the above-mentioned slurry polymerization process is preferably from 1 to 500 g-solid catalyst component/liter-solvent, and particularly preferably from 3 to 300 g-solid catalyst component/liter-solvent. A pre-polymerization temperature is preferably from xe2x88x9220 to 100xc2x0 C., and particularly preferably from 0 to 80xc2x0 C. A partial pressure of the olefin in a gas phase of the pre-polymerization is preferably from 0.01 to 20 kg/cm2, and particularly preferably from 0.1 to 10 kg/cm2. However, said partial pressure is not limited to an olefin, which is liquid under the pressure and at the temperature of the pre-polymerization. A pre-polymerization period of time is not particularly limited, and preferably usually from 2 minutes to 15 hours.
As a method for feeding the solid catalyst component, the organoaluminum compound and the olefin into a pre-polymerization vessel, there are exemplified (1) a method comprising the steps of feeding the solid catalyst component and the organoaluminum compound, and thereafter feeding the olefin, and (2) a method comprising the steps of feeding the solid catalyst component and the olefin, and thereafter feeding the organoaluminum compound. As a method for feeding the olefin to a polymerization vessel, there are exemplified (1) a method comprising the step of feeding the olefin successively so as to keep a pressure in the polymerization vessel to a pre-determined degree, and (2) a method comprising the step of feeding a pre-determined total amount of the olefin at the same time. In order to regulate a molecular weight of the olefin polymer obtained by the pre-polymerization, a chain transfer such as hydrogen may be used.
If desired, the above-mentioned external donor (namely, outer donor) may be used in the pre-polymerization. An amount of the outer donor used in the pre-polymerization is usually from 0.01 to 400 mol, preferably from 0.02 to 200 mol, and particularly preferably from 0.03 to 100 mol, per 1 mol of the titanium atom contained in the solid catalyst component, and usually from 0.003 to 5 mol, preferably from 0.005 to 3 mol, and particularly preferably from 0.01 to 2 mol, per 1 mol of the organoaluminum compound.
In the pre-polymerization, a method for feeding the outer donor into a pre-polymerization vessel is not particularly limited. As said a method, there are exemplified (1) a method comprising the step of feeding the outer donor only, and (2) a method comprising the step of feeding a contact product between the outer donor and the organoaluminum compound. The olefin used in the pre-polymerization may be the same as or different from that used in the real polymerization in its kind.
As a method for the real polymerization, there are exemplified (1) a method comprising the step of polymerizing the olefin in the presence of a catalyst obtained by contacting the solid catalyst component, the organoaluminum compound and the outer donor with one another, (2) a method comprising the step of polymerizing the olefin in the presence of the pre-polymerized catalyst, and (3) a method comprising the step of polymerizing the olefin in the presence of a contact product among the pre-polymerized catalyst, the organoaluminum compound and the outer donor.
An amount of the organoaluminum compound used in the real polymerization is usually from 1 to 1000 mol, and particularly preferably from 5 to 600 mol, per 1 mol of the titanium atom contained in the solid catalyst component.
An amount of the outer donor used in the real polymerization is usually from 0.1 to 2000 mol, preferably from 0.3 to 1000 mol, and particularly preferably from 0.5 to 800 mol, per 1 mol of the titanium atom contained in the solid catalyst component, and usually from 0.001 to 5 mol, preferably from 0.005 to 3 mol, and particularly preferably from 0.01 to 1 mol, per 1 mol of the organoaluminum compound.
A polymerization temperature in the real polymerization is usually from xe2x88x9230 to 300xc2x0 C., and preferably from 20 to 180xc2x0 C. A polymerization pressure is not particularly limited, and from an industrial or an economical point of view, it is generally from atmospheric pressure to 100 kg/cm2, and preferably from about 2 to about 50 kg/cm2. A polymerization manner may be either a batch type or a continuous type. As a polymerization process, there are exemplified a slurry polymerization process using an inert hydrocarbon solvent such as propane, butane, isobutane, pentane, hexane, heptane and octane; a solution polymerization process using said solvent; a bulk polymerization process using an olefin as a medium, which olefin is liquid at a polymerization temperature; and a gas phase polymerization process. In the real polymerization, a chain transfer agent such as hydrogen may be used in order to regulate a molecular weight of the olefin polymer obtained.